Current understanding of treatments and outcomes of chronic lymphocytic leukemia (CLL) and non-Hodgkin’s lymphoma (including mantle cell lymphoma (MCL), Waldenström macroglobulinemia (WM), follicular lymphoma (FL), marginal zone lymphoma (MZL) and diffuse large B-cell lymphoma [DLBCL]) patients in Finland is limited. FINLeukemia study will address these outstanding questions utilizing data from national registries and regional data lakes in a 3-phase non-interventional RWE study.